Cool Tools: Measuring Tools

The tape measure is a basic tool for integrated systems installers, electricians and professionals in many trades. It has been in use for years, but the measuring tapes available today are nothing like early versions. The improvements are examples of how a simple, basic tool evolves to do its job better, function easier and be more durable. While laser distance-measuring tools are growing in popularity, the not-so-humble tape measure still is best for multiple measurement tasks.

Most popular with integrated systems installers and electricians are 25- and 30-foot models. A steel tape’s “stand-out” length defines how far the blade will extend without bending.

Hardware stores and home improvement centers carry a wide selection of low-cost tapes, but most professionals recognize the value of paying a little more for the features and durability of professional models. Well-known suppliers in the industry are DeWalt (www.dewalt.com), Greenlee (www.greenlee.com), Ideal Industries (www.idealindustries.com), and Klein Tools (www.kleintools.com).

Typically, installers of alarm, surveillance and control systems use tapes to take measurements for exact spacing between alarms or sprinklers and for positioning between joists or 2-by-4s for junction boxes and relays, said John Fee, Greenlee senior product manager.

“Stainless-steel tape measures today are designed with either a click-lock or auto-lock feature for easy readings,” Fee said. “Most have a tough, impact-resistant ABS case that’s over-molded for added protection. The double-sided tape comes with markings on both sides, so it can be read from above or below. Markings vary, but some include key markings an electrician needs daily, such as a mark with the exact height an electrical outlet would be positioned on a wall. Most feature 1-inch-wide tape blades with some type of coating—typically Teflon—to ensure smooth pay out and retraction.”

Marina Wolk, Klein Tool’s product manager for measuring tapes, said that, over the years, various features have been incorporated in tape measures primarily to improve functionality and durability.

“Examples include oversized bold numbers for easy reading, fraction symbols denoted for quick references, for example ¼-, 3/8-, ½-, 16-inch stud and 19.2-inch truss measurement indicators, along with markings on both sides of the tape for measuring flexibility,” she said.

Because the backside of the tape contours well to pipes, a second hook facilitates measuring conduit or other surfaces, Wolk added. Additional feature updates include larger end hooks with rare earth magnets for stronger hold, nylon-coated blades to resist abrasion and wear, and steel belt clips for durability.

“Some of the more recent innovative features that make the job easier are clean corner access for flush-edge measurements as well as a ‘true zero’ feature for accurate inside and outside measuring,” she said.

Cases are more job-friendly and durable.

“Not only are cases more shock- and impact-resistant,” Wolk said, “they also are more stable for balancing the case on various sides as well as different surfaces. For easy one-person measurements, rubber housing on the case provides a slip-resistant, comfortable grip. To protect against scuffs and promote easy gliding along multiple surfaces on the job site, nonmarring foot slides have been added to help maintain a clean work surface.”

To increase longevity of the tape measure, a release system allows users to adjust the speed of the rewind.

“The retraction speed can be regulated by simply tilting the angle of the tape when it is being rewound,” Wolk said. “This also decreases the chance of hooks breaking, the tape being sheared and fingers being slammed.”

Accessories available to carry tape measures include leather and nylon tape holders and pouches that attach to belts.

Most alarm and control length measuring requirements range from a few inches to 30 feet, and compact tapes usually are best. For longer distances, steel tapes to 100 feet are available, while soft tapes and measuring wheels are options. Made of flexible material that hangs loose and is wound on a reel, soft tapes are good to use when multiple markings need to be made along the length being measured.

Rolling distance measuring wheels also are good for longer distances and enable the user to mark intervals along the route. The user rolls the wheel along the route to be measured and accumulated feet are displayed in a window similar to a car’s analog speedometer reading.

Although most measurements with soft tapes and wheels are made outside of structures, they can be useful on large commercial jobs.

Laser and other tools

“Laser tools are handy when one person must take measurements, especially over long distances,” Wolk said. “Another benefit of laser tools is that they allow installers to store measurements taken and even add stored measurements together for a total measurement. These features can be helpful when estimating supplies for a job.”

However, Wolk said, laser devices are not as precise as manual tape measures and should not be used when accuracy is imperative. Another downside to laser measurement is the necessity of an end point to register the laser.

“For example,” she said, “if the full length to a wall is being measured, it is a quick tool to use. But if the measurement needed is one-third of the way to the wall, a manual tape will be needed because there is no ‘barrier’ to stop a laser beam at that point.”

Vivian Fahey, laser distance meter marketing manager at Fluke Corp., said that security system installers also use laser distance meters to measure building dimensions, verify CAD drawings (or create as-built dimensions), and to help calculate quantity of materials required—all to assist bidding a job as quickly and accurately as possible.

“Specifically,” she said, “laser distance meters allow contractors to electronically measure height and width by triangulation if needed and to calculate area and volume on the fly.”

“They even measure the cable remaining in a box or on a reel,” Wolk said. “Accuracy of these meters is up to +/–1 percent. These new products can save time and money on the job site, allowing installers to work more efficiently when installing or repairing wiring infrastructure for security and access control systems.”